The Diminished Scale (colour code chart here)
The notes in the above 2 octave diminished scale are:
As a result of the intervallic structure there are only 3 diminished scales, if you play the above 2 octave pattern but start on the 6th fret (D#) followed by playing
it on the 9th (F#) and the 12th (A) you find the same notes from the C diminished, however, technically these scales would be called D#, F# and A diminished
respectively.
What that means is you could look at the C diminished scale as also being a D#, F# and A diminished scale, ultimately it’s the same scale but whatever note we treat as
the root should therefore name the scale. This process works the same if you take C# diminished as the starting point and move the pattern up every 3 frets as it does
for D diminished and when you start from D# diminished you are back to where you started, repeating notes of the C diminished scale.
There are 2 ways of playing the scale and they are:
Tone - Semitone - Tone - Semitone - Tone - Semitone etc…
This construction is sometimes referred to as the whole/half step diminished. (see pattern at top of page)
Semitone - Tone - Semitone - Tone - Semitone - Tone etc…
This construction is sometimes referred to as the half/whole step diminished.
The diminished scale is used with a diminished chord but has a lot of other possible applications. We are now going to look at some of those applications, firstly,
here is the half/whole step diminished scale
The notes in the above 2 octave diminished scale are:

1

3

5

1

3

1

5

3

5

C

C#

D#

E

F#

G

A

A#

C

C#

D#

E

F#

G

A

A#

C

If you look at the scale carefully you can see notes that form major and minor triads. Let´s concentrate on the major triads for a moment:

C

E

G

=

C MAJOR TRIAD

A

C#

E

=

A MAJOR TRIAD

D#(Eb)

G

A#(Bb)

=

Eb MAJOR TRIAD

Diminished Example 1
This next example also utilises the major triads found in the diminished scale by sweep picking a regular open A major shape found at the bottom of the neck of the
guitar and moving it up every 3 frets.
Diminished Example 2
You can apply the diminished scale over other chords as a substitution. Take the V chord in a major or minor II V I, if you understand the
II V I chord progression you will know
that the V chord can be substituted in the case of a II V I in the key of C major from G7 to G7b9, G13b9, G7#5 etc…
Lets have a look at the G h/w diminished:
The notes are:
G G# A# B C# D E F G
and the construction of a basic G7b9 chord is:
G B D F G#(Ab)
As you can see the notes that make up a G7b9 chord can be found in the G half/whole step diminished scale, consequently the G half/whole step diminished scale will
work as a substitute for the G altered scale. This leads us to the subject ofscale substitution say you are playing over a G7 vamp, in your solo you could substitute G half/whole step diminished
for G mixolydian. At first this might sound very strange when played over a regular G7 chord vamp, but stick with it because it is a useful device and introduces you
to the kind of ‘outside sound’ that you can hear in some styles of jazz.
It can be quite a challenge to improvise with the diminished scale and to create a melodic statement that goes beyond patterns that are usually relied upon when a
diminished chord comes round. It is possible to avoid the usual clichés by approaching it angularly; that is to make wide intervals between notes, for this you need to
have a solid right hand technique. Below I have two examples for you to try, as always, if it's tough to play, start slow and then speed up and remember your good
friend the metronome.
Diminished Example 3
Diminished Example 4
At this juncture I would like to bring to your attention that the best way to increase your
technique is to transcribe players of
instruments other than the guitar. The purpose of doing this is that the mechanics of other instruments are different and therefore the choice of notes,
and when you transcribe the solo, the notes you hear and play on the guitar steer you away from playing the normal guitar type habitual finger patterns.
There is a wealth of inspiration to be discovered in the solos of some of the great musicians that have graced our ears, and transcribing will not only improve your
technique and ability to hear but the ability to improvise within the given genre.